Here's a bit of life advice for you: It's never a good idea to insult the man with a gun to your head. But for many defiant TV characters in deadly situations, there's no need to be afraid of the man with the proverbial gun. Year after year, TV shows introduce us to characters who want to kill someone, but can't kill them because they are of more use alive. From drug lords to vampires, these TV characters are torn between their desire to kill someone and the desire to profit from that person's knowledge.
Gus Fring, "Breaking Bad"
Throughout all of Season 4, Gustavo Fring wants nothing more than to kill Walter White. Walt has utterly ruined the plans that Gus had for the business, and Walt's disobedience infuriates Gus to no end. But Gus can't kill Walt: Walt is the only man in America who can produce meth that's 99.2 percent pure. The entirety of Season 4 turns into a big game of cat and mouse. Gus wants Walt dead because he's a loose cannon, while Walt wants Gus dead in order to gain his freedom.
Klaus, "The Vampire Diaries"
Klaus loves killing people, but he is capable of restraint when it serves a greater purpose. He wanted nothing more than to kill Elena in earlier seasons but stayed his hand until he could attempt to kill her in a ritual that would unlock his full power.
In the current season of "TVD," Klaus is once again showing restraint. He has captured a vampire hunter and wants nothing more than to kill the man. However, he needs to keep the hunter alive, as the hunter's body is covered in a magical tattoo treasure map that will disappear as soon as the hunter is killed.
Sydney Bristow, "Alias"
Sydney became a double agent after her boss at SD-6, Arvin Sloane, had her fiance murdered. She wants nothing more than to kill Sloane in revenge for killing the love of her life. However, Sydney is able to resist the urge to kill Sloane because she needs him alive in order to gather intelligence about SD-6. If Sloane dies, she will never get the information she needs to take down their syndicate for good.
Jack Bauer, "24"
There are few people in the world that Jack despises as much as Nina Myers. That's because Nina killed Jack's wife. Despite this fact, Jack has to restrain his impulse to kill Nina during Season 2, when the two are forced to cooperate in order to combat a terrorist threat.